Renewable fuse



Feb. 17, 1931. p -J cp Ns 1,793,318

RENEWABLE FUSE Filed March 25, 1928 INVENTOR terminal blades,

Patented Feb. 17, 1931 UNITED STATES PATENT OFFICE PETER J. HOPKINS, OF PITTSBURGH, PENNSYLVANIA. ASSIGNOR TO GREAT WESTERN FUSE COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF DELAWARE 1 RENEWABLE rUsE Application filed March 23, 1928. Serial No. 264,142.

The object which I have in View is the provision of a renewable fuse of simple and inexpensive mum number of parts; easy to assemble, disassemble and renew Without the use of tools and by unskilled persons, and whose ends are sealed against the outward travel of flames along the terminal blades.

In the accompanying drawings, wherein I have illustrated the best embodiment of the principles of my'invention now known to me, Fig. 1 is a longitudinal section of the fuse.

Fig. 2 is an end view of the same looking from the left in Fig. 1 and with the screw cap removed and the sealing disk rotated into its operative position.

Fig. 3 is a like view with the sealing disk removed.

Fig. 4; is an end view of one of the ferrules. Fig. 5 is a face view of the rotary sealing disk.

Fig. 6 is an inner washer.

Fig. 7 is an inner end view of one of the the right hand terminal illustrated in Fig. 1.

Fig. 8 is a side elevation of the other terminal blade, the left hand one in Fig. 1.

Fig. 9 is an inner end view of the last mentioned terminal blade.

Fig. 10 is an end view of the fuse, the terminal being shown in section along the line 10-10 in Fig. 8 and a modified form of sealing disk being shown in use.

Fig. 11 is a face view of the sealing disk shown in Fig. 10.

Referring to the tubular shell of the face View of the slotted drawings, 1 indicates the I material such as fibre.

On either end of the fuse is mounted a metal ferrule 2, the two ferrules being preferably identical in structure and being fixed to the shell as by threaded engagement and riveting.

The ends of the ferrules are recessed at opposite points to provide the seats 3..

The ferrules are exteriorly threaded to receive the two annular metal end caps 4.

The shell and its end ferrules form the tubular body of the fuse.

construction; comprising a mini fuse, made of insulating 5 and 6 indicate the'two metal terminal blades whose inner ends are of reduced width and are attached to the ends of the fusible link 7. A

One of the terminal blades, 5, the right hand blade in Fig. 1 has fixedly mounted thereon the circular metal closure head 8 which fitsagainst the end .of the ferrule at the corresponding end of the fuse body.

The head 8 is providedon its inner face with a transversely disposed rib9 whose ends engage the seats 3 and thus prevent rotary movement of the head and terminal blade relative to the fuse body.

The other terminal blade 6 is provided with a fixed metal abutment 10 which extends on either side of the blade and whose outer face is substantially flush with the fuse body when The washer is provided with lugs 14 on its the seats 3 in the inner face which engage ferrule 2 and thus prevent rotary movement of the blade and washerrelative to the fuse body.

15 indicates a circular sealing disk having a circular aperture 16 in its center of sufficient diameter to clasp the restricted neck of the blade 6 between the notches 11.

At two diametrically opposite points the wall of the aperture is notched out as at 17 to enlarge the aperture sufficiently to permit the sealing disk, when turned into the proper position, to be slipped down over the blade 6 and to rest against the outer face of the washer 12.

The disk in then rotated until the concentric wall of the aperture 16 engages the notches 11.

' The notches 11 are of suifieient width so that i --when slipped down over the blade the disk the side of the slot in the washer 12 from within, and that the disk 15 seals the end of said slot from without, so that the flames cannot travel outwardly along the terminal blade 6. I

To assemble the fuse, the terminal blades .5 and 6 are connected to the ends of the fusible link 7 and the blade 5 inserted through the fuse body from the right in Fig. 1 until the closure head 8 seats against the end of the fuse body with its rib 9 engaging the seats 3.

The slotted washer 12 is then slipped down over the blade 6 until it rests on the abutment 10 and the end of the fuse body with its lugs 14 engaging the seats 3.

The sealing disk 15 is then slipped down over the blade 6 against the washer 12 and then rotated until it engages the restricted neck of the blade, as illustrated in Fig. 2.

The cap 4 is then screwed down into place on the fuse body.

To d'sassemble the fuse, the left hand cap a in Fig. 1 is first removed and the sealing disk rotated to release it and then slipped off the blade 6.

The slotted washer is then slipped ofi the blade.

The cap 4 is then unscrewed from the other end of the fuse body,.thus releasing the closure head 8 and the blade 5.

v In Fig. 11 I show a sealing disk 15a having an irregular shape aperture 16a which when the disk is turned in one direction relat1ve to the blade. 6 permits the disk to be slipped down over the blade and rest against the slotted washer 12 and which when the disk is rotated into its position shown in Fig. 10 will cause the walls of the aperture to enter the notches 11 in the blade 6 and Wedge against the edge of the restricted neck of the blade, thus wedging the disk iniits sealing position.

It is evident that my improved renewable fuse has but relatively few parts, all of simple and inexpensive character, that it may be quickly and conveniently assembled, disassembled and renewed by an unskilled person and without tools.

- It is further evident that the outward escape of flames along the terminal blades is prevented. f

What I desire to claim is 1-- 1. In a renewable fuse, the combination of a tubular fuse body, a terminal blade arranged to extend through the end of said body, an abutment on said terminal blade eX- tending outwardly from the sides of the blade, the blade being provided with a re stricted neck outside of said abutment, a

slotted washer arranged to be slipped down to the axis of said disk which when the disk is rotated relative to they washer become wedged against the edges of the restricted neck, thus sealiugthe ends of the slot of the washer, and means for clamping the disk to the washer and the washer to the end of the fuse body.

2. In a renewable fuse, the combination of a tubular fuse body, a terminal blade arranged to extend through the end of said body, an abutment on said terminal blade extending outwardly from the sides of the blade, the blade being provided with a restricted neck outside of said abutment, a slotted washer arranged to be slipped down over the terminal blade to rest against the abutment and close the end of the fuse body, a fiat sealing disk having a central aperture enlarged at diametrically opposite points to permit the disk to be slipped down over the terminal blade and rest on the washer and the edges of said aperture between its enlarged portionsbeing disposed eccentrically to the axis of said disk which when the'disk is rotated relative to the washer become wedged against the edges of the restricted neck, thus sealing the ends of the slot of the washer,and an annular cap arranged to be screwed onto the end of the fuse body to clamp the disk to the washer and the washer to the end of the fuse body. Signed at Pittsburgh, Pa., this 20th day of March, 1928.

PETER J. HOPKINS. 

